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Large World Construction Issues

Hi,

Looking for some general feedback and ideas before undertaking creating a new world. What I am trying to do is create a very realistic world map for a fantasy world. The world will be approximately the same dimensions as earth. The diameter will be 16,200 leagues. I am contemplating creating a map 16,200 pixels by about 6300 pixels which would cover the entire globe east to west and to about the 70th parallel north to south. I realize that the map will be stretched at the north and south but I'm not concerned with that. I do plan on having at least 16 climates using rainfall and wind patterns to make it very realistic. That part is no problem either. There will be at least 11 major races and many minor ones with a total population of about 400 million. I could make a good looking map with a lot less pixels but I want to place a lot of population centers and want them to be relatively realistic, There will be lots of borders and rivers etc. Since a league is about 1.5 miles even at the resolution mentioned every border I draw is a mile and a half thick. I plan on using GIMP and am getting warnings about file size when I create the new file.

Please share your thoughts maybe there is a much easier way to do this.

What do you mean stretched? What map projection are you going to use ?

The only warning I receive with Gimp is that the file is too large but you can increase the limit in the options. Still. I'm suprised a file with these dimensions is over 1 gb. I had files twice that big in photoshop that were far from 1 gb.

What do you mean stretched? What map projection are you going to use ?

The only warning I receive with Gimp is that the file is too large but you can increase the limit in the options. Still. I'm suprised a file with these dimensions is over 1 gb. I had files twice that big in photoshop that were far from 1 gb.

I wasn't going to use a projection I'm just going to have a basic rectangular map. If that makes sense.

I wasn't going to use a projection I'm just going to have a basic rectangular map. If that makes sense.

No, all maps are in a projection. They all have distortion. If you're as adamant about being realistic as you say, this is something you need to get right from the beginning otherwise any later effort you put into realism is pretty much pointless.

Craig V. this is am ambitious as my Zigoto Map. I ended up giving up on the project because of the complexity. I would start by learning about plate tectonics and then make a map based on that work. Once you get a planet formed, you can figure out the climates of the various regions on it. You might not like the initial outcome, come there will be regions you will like working with. This sounds like a huge project that might require a few people to help you with. I would love to see how this turns out.

What Hai Etlik says is true. A round sphere put onto a rectangular flat shape will always have some distortion. You should figure out which type of projection you want to use as there are many options or just go without. This will be relevant for distances because a horizontal line of the same length at the top of your length will cover more distance than if near the equator for example. How your world is spaced out will have political and economic implications if you want to be realistic. Otherwise don't worry about it too much. For example I did not consider projection for my Skenth map initially and got too far along to implement it later.

Your map sounds quite ambitious in size! All that really matters is if your computer can handle working on such a large image smoothly. If you want to print your map such a large map will be useful however as even at 300 dpi such a map size handily fills up many poster sized prints and everything smaller.

For example, a common poster size is 18 x 24 inches and this is 5400 by 7200 pixels if you use the very common resolution of 300 dpi. You may not need to go over that or if the map doesn't need to be super crisp you could set it to 200 dpi to require even fewer pixels to fill such a print area physically. You should ask yourself how large of an image you really need and what you want to do with the image.

It sounds kind of moot since gimp won't even run such a large file but if you can get a hold of another software program like photoshop it may be able to hold larger images.

I would recommend testing your computer's ability to run such a large image first. Create an image of the desired size and fill it with photos and whatever images, exactly what does not matter as you just want to cover the entire canvass as you don't want it to be just one colour as that is easy to compute. Then flatten everything into one layer, copy and paste it a couple of times (maybe 10 to 20 times) and then start playing around with things. Try rotating layers, painting things, adding text, selecting and such. What will probably happen when you are working on your map is you'll have a bunch of layers with a lot of pixel data on them and you'll want to emulate this.

If you find the computer slows down after a while you may (especially in terms of loading and saving by the way) want to consider a smaller size. Increasing the size of an image an image has a non-linear demand on system resources by the way. Increasing a map from 18 x 18 inches to 20 x 20 inches is a lot more taxing than increasing it to 19 x 19 inches. The same of course goes for pixels.

Aside from reducing the size of your image there are a few things you can do to keep the file size and demand on your ram down. One thing you can do is keep your layers to a minimum keeping only the ones you really need and not preserving hundreds of unnecessary layers. Learning what you can merge down and what you may want to keep separate is a bit of an art but it comes with experience. The second thing you can do is reduce the number of undos your software keeps track of. Obviously a shorter history will demand less on your RAM. If I am not mistaken, creating an image in the RGB colour mode may be less intensive than CMYK mode but that is conjecture only based on the observation CMYK images tend to be larger than RGB. There are other things I can't think of and other people may know a few things!

If you are really set on being able to create really a large image you may want to venture into vector art which has a number of limitations and works differently that rasterized (pixel ) art.

The stress testing is just to figure out what your computer can handle so if your machine can handle the shock test at the size you desire, it's all happy sailing What cultures, histories, and such you want to have are up to you. I would look into historical precedent for things of course. Consider sites like this as a reference point.

I don't have nearly half as much expertise in map-making as most of the folks in this community, but I find the issue of projection to be a vexing one, since any maps I create are intended to be viewed flat, either as a printed image, or as a static image on screen. Honestly, I think my most likely technique will be writing off the polar regions and focusing on more equatorial landmasses, where the distortion is not nearly as noticeable. I'm also likely to break up my landmasses so I can view each in totality and kind of forget, for the moment, how the world wraps around on itself. It is one thing to map a region or a continent without thinking of the total globe. Mapping a globe required a different kind of thinking altogether.

As I'm currently working on a 48000 * 24000 world map, I think the single biggest lesson I've learned is not to start big. When you start with a large map (a really large one) you run into a few very big issues.

1. It's hard to keep track of the overall shape of your world. This is particularly problematic with coasts.
2. It's basically impossible to make quick revisions when your world is being done large from the ground up.
3. Most importantly, you will get fatigued and burned out when you're spending hours just trying to draw the coasts or pick out deserts or what have you.

I've found that the way to go is to start smaller. Maybe a few thousand by a few thousand pixels. Do a complete world map. You won't have much detail, but you'll be able to get one done, and figure out the overall climates and ethnic groups and what have you. You'll be able to identify, earlier on, what kinds of problems you have with it and what you want to change. Most importantly you'll have something nice to look at and think about from the start, so even when you're doing the next size up, you won't be rushing to see what it looks like and possibly making poor, sloppy decisions.

In other words, go up in size in stages.

Regarding projections, generally speaking once I have an initial draft done (I favour equirectangular, personally) I'll load it up into NASA's G.projector and use one of the polar projections (specifically, Orthographic centered on 90 or -90 degrees North) to get a circular map of the north and south poles.

I'll then pop those back into photoshop, note the problematic distortions that will invariably have arisen, and do a sketch over on a new layer, how I actually want the land and water on and around the poles to look. I then select the entire image (so that the next step works properly) and do a Polar to Rectangular distort on the sketch layer.

I can then take this and use it as a guide for how the polar regions should actually look on the equirectangular map when the time comes to do my next size up. Generally, for a square image (such as the polar sketch image) to a rectangular image (such as the equirectangular main map) the polar sketch will need to be stretched all the way across the map, but only halfway down. This will fit it properly. One may also need to include a plain white layer with it so that your selection is properly sized; if it just sticks to the sketch you're liable to have some inaccuracies.

You can then draw polar regions in an equirectangular map that actually look how they should.

I just worked on a 10,000 x 5000 pixel size map in GIMP myself and have to agree with the other here that having such a large map may be pointlessly troubling. Towards the end Gimp and my computer was starting to struggle with it, which when you are tried can make editing really frustrating. It ended up being just under a gig in size. You also have to consider what a map is about, a world map is about presenting large scale general information, for a finer understanding about areas on the map people use correspondingly smaller and smaller scales (or larger and larger... what? no that can't be right..). So you have to question whether having a world map in which you can see every river or field or populated area is really what you want to work on in a world map. And if not then you could cut away much of that size. If I were to redo the map I'd think I'd use the Poster size Viking suggests or something with around the same total area. Sometimes good enough is just perfect, all art is about editing. Cheers

ViewingDale was specifically written to address these large world building problems. It is true that paint packages where the whole world is on one giant bitmap is a silly idea and you will run into numerous problems. You need a world manager like this to handle that complexity. I have the middle earth medem map at 40K res in viewingdale no problem and it has had a 100K pix square image in it and its still fine. Below are videos of it running the CWBP - the community world building project from this website.